She's not all there, so there's no need to hurt him.

My mom was recently diagnosed with cancer that has moved to her brain. This has significantly changed her personality. I was recently planning a visit to see her (she lives several hours away) and she forcefully told me not to bring my husband, that she can’t stand him and he exhausts her. This is causing me extreme anxiety. How do I explain to my husband, who loves my mother, that she doesn’t want him around? He has been very accommodating with my visits, but if I tell him that she doesn’t want him around at all, it will hurt his feelings tremendously. He understands logically that she isn’t completely herself right now, but it is still hurtful.